I just replaced the drive shaft center support bearing, rubber bearing mount and all 3 U-joints on my 86 244 (200k mi). I was getting a "bearing roar" at 50 mph and above and suspected the center bearing. The old bearing did seem to feel rough when I turned it by hand and the roar noise is now gone so I feel good about that. The problem is now, I get a low frequency body vibration (a low frequency, total body rumble) at 56-60 mph, that did not exist before. It goes away at higher speeds and is much more pronounced on deceleration as opposed to going up through the 56-60 mph zone. I was careful to mark (with a scribe) and keep the orientation the same on all the u-joint yokes, the spline of the shaft, and the trans and diff flanges. I didn't clamp or squeeze the drive shaft, but I did use a vice to press out the u-joint cups. Is it possible to warp/bend the yokes out of alignement like this? Could the rear axle bearings (outboard) or differential cause this? Neither of them have been repaired or replaced. Any ideas???